Champion Power Equipment 50-Amp RV Generator 30-ft / 1 3-Prong Outdoor Heavy Duty Locking Extension Cord in the Extension Cords department at Lowes.com
VEVOR 50 Amp 10-50ft RV/Generator Power Cord N14-50P to Bare Wire Extension Cord | eBay
Amazon.com: 50A RV Extension Cord and 50A Y Splitter Cord : Automotive